A portable electronic device is typically a small computing or communicating device with a display. A portable electronic device typically can run various types of software applications, known as apps. Most portable electronic devices can also be equipped with Wi-Fi, Bluetooth and Global Positioning System (GPS) capabilities that allow connections to the Internet and other Bluetooth capable devices such as a vehicle or a microphone headset. A camera or media player feature for video or music files can also be found on these devices. A portable power supply such as a lithium battery is typically used as the power source. Examples of portable electronic devices are smartphones (e.g., iPhone® of Apple Inc.), tablet computers (e.g., iPad® of Apple Inc.), wearable computers (e.g., Google Glass of Google), and watch phones (or smartwatches).
Some portable electronic devices are configured to perform speech (or voice) recognition function for interacting with a user's voice command. Typically, activating a voice command interface on a portable electronic device requires a physical action by the user. For example, to activate a voice command interface on a portable electronic device, the user may be required to press or hold a real or virtual button (or switch) on the portable electronic device. This physical activation of the voice command interface is troublesome, and sometimes dangerous, for example, when the user is driving a vehicle.
Alternatively, a voice command interface on a portable electronic device can continuously run as long as the portable power supply is providing power source to the portable electronic device. Although this is convenient to the user, however, a continuously run voice command interface wastes battery power when voice command interface is not required. This may be due to the fact that in order to perform voice command interface, a portable electronic device typically requires at least a microphone, an Analog-to-Digital Converter (ADC), a signal processor, a Digital-to-Analog Converter (DAC), a speaker, and other digital or analog circuits to be put in work and they are typically power consuming.
Alternatively, a voice command interface on a mobile computing device can be activated and continually run when the device is receiving power from an external power source, while the voice command interface is deactivated when the device is not receiving power from an external power source. Although this type of configuration conserves battery power, however, this type of configuration lost its portability because the voice command interface is only activated when the device is receiving power from an external power source.
In addition, a continuously run voice command interface may annoy or interrupt the user when the portable electronic device accidently “hears” a false command, which may be generated from the environment, and attempts to interact with the user. In addition, on some occasions, the user may not want private information to be played by the portable electronic device when other people are around.
Therefore, it would be desirable to have a portable electronic device that physical activation of the voice command interface on the device is not required, battery power can be saved when the voice command interface is not required, the voice command interface can be activated without relying on external power source, the user may not be interrupted by the portable electronic device accidently, and the user can control whether the content of the message is to be shared with other people around.